<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    function Foo(){
    }
    let f = new Foo();
    console.log([Foo])
    console.log(Foo[Symbol.hasInstance](f))
</script>
</body>
</html>